Preheat oven to 130C.
Mix the flour & the sugar in a bowl. Add the diced butter, rubbing in with your finger tips until the mixture resembles course bread crumbs. Add the egg yolk and the water, and mix until the pastry forms a paste. Wrap the dough in glad wrap and leave in the fridge to rest for 30 minute
In a medium sized bowl, whisk together the eggs, sugar and lemon juice. Add the goats curd, cranberries and refrigerate until cool.
Line a flan ring with baking paper. Roll out the pastry to fit into the flan ring and place in the oven and blind bake for around 15 minutes.
Pour the curd mixture into the shell and bake for 20 minutes or until set. Allow to cool and serve with creme fraiche.